This experiment from Volume Labs demonstrates how to send data between two points without the use of RF (radio frequency) or a wired connection. One computer is translating a text file into a series of QR Codes and displaying them to a screen. The files are divided up into small packages since a QR Code can hold a max of 3Kb or around 4,000 characters. The second computer is performing change detection on input from a camera and translating the QR Codes back into a file.
I see three potential applications of this technology.
Unidirectional Data Transfer
One use would be the unidirectional movement of data between networks. It is often called a one-way transfer device or a data diode. One-way transfer systems are used to protect a network or computer against viruses, outbound transmission of data, and other cyber attacks. One business that uses one-way transfer systems is the power generation industry. To protect the power grid, there should be a gap between the internet and the power control systems.
Data Transfer To/From Faraday Cage
Another application of this technology is sending data visually in or out of a Faraday cage without introducing an RF leak.
Long-Distance Data Transfer
Another use is to transmit data over a larger distance using a camera with a telephoto lens.
It could be used to send data between devices, share large documents to a wide audience, or transmit additional data alongside a television broadcast. This is accomplished using an open source package called Zxing. The QrCodeTransfer code is available at github.
Additional Reference added 4/30/2014:
- QuickeR: Using video QR codes to transfer data